#include<stdio.h>

double pot(double x, int n){
                           if (n == 0) return 1;
                           else return x * pot(x,n-1);
                           }

int main(){
			double k = 1;
			int i=1;
						
						while(i <= pot(10,6)){
						k = k*pot((2*i),2)/(pot((2*i),2)-1);
						i = i+1;
						}
    
			printf("El valor de pi es %lf \n\n",2*k);
return 0;
}
